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Adult, dark phase, Riverside County. |
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Adult, Riverside County |
Adult, Imperial County |
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Adult, dark phase, Riverside County. |
Light phase adult, photographed while active at night
on the face of a massive boulder, Imperial County. |
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Light-phase adult, photographed while active at night, coastal San Diego County. |
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Dark phase adult, 7,500 ft. San Jacinto Mountains, Riverside County, found hiding under a rock during daylight. |
Dark phase adult and Juvenile, found hiding together under a loose rock slab
during daylight, coastal San Diego County.
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Habitat, Imperial County |
Microhabitat, exfoliated granite under huge boulders
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Habitat, Riverside County |
Habitat, coastal Riverside County |
Habitat, San Diego County |
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Habitat, San Diego County
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Habitat, Riverside County |
Habitat, 7,500 ft., Riverside Co. |
Short Video |
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Watch a short video of this lizard running in bursts of speed in a serpentine motion.
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| Description |
| Size |
| 2 - 2.75 inches long from snout to vent (5.1 - 7 cm). (Stebbins 2003) |
| Appearance |
A small lizard with a flattened body, a flattened head covered with large plates, soft skin with fine granular scales, lidless eyes with vertical pupils, a gular fold, a fold of skin low on each side of the body, and a long thin tail, except when it has been detached and has only partially regenerated. Males have enlarged femoral pores and a whitish oval patch on the front edge of the line of femoral pores.
In the light phase, the color is white or yellowish with large dark brown spots on the upper surfaces, and irregular spots and bands on the tail. In the dark phase, the color is dark brown with pale white or yellow network on the upper surfaces. This lizard is capable of quickly changing from light to dark phase.The underside is whitish with minute black speckling, and is made up of large square scales in 14 lengthwise rows. |
| Behavior & Natural History |
Nocturnal. Wary and secretive. Hides in crevices, under rock flakes and slabs, rarely going out except at night when it can be seen crawling on the face of boulders and sometimes on cement structures and buildings. Most active spring through fall, sometimes active on warm winter days. May be active in crevices during daylight. Changes from dark phase during the day to light phase at night.
Although this lizard prefers similar habitat to the Leaf-toed Gecko, Phyllodactylus xanti, the ranges of these two species rarely overlap and when it does, they almost never share the same microhabitat. |
| Diet |
| Eats small invertebrates including spiders, scorpions, beetles, ants, and centipedes, and possibly lizard eggs and a small amount of plant material. |
| Reproduction |
| Breeds in late spring. 1 - 2 young are born live in the fall. |
| Range |
| Found from the southern side of San Gorgonio Pass, south through the Peninsular Range, including both the eastern and western slopes, into northern Baja California as far south as the Canon el Cajon divide in the Sierra San Pedro Martir. Also occurs west of the mountains in the Lake Perris and Lakeview Mountains area. |
| Habitat |
Inhabits rocky canyons and hillsides in the desert and in semiarid regions, and sometimes coastal sage with no large rock outcrops. Prefers massive boulders and outcrops with exfoliated granite found in the shadier parts of canyons or near water. Tends to avoid hotter south-facing slopes. Vegetation includes chaparral, coastal sage scrub, creosote scrub, woodland, and manzanita and coniferous forest at high elevation locations.
400 - 7,600 ft. (120 - 2,320 m). (Stebbins 2003) |
| Taxonomic Notes |
| Called Xantusia henshawi henshawi - Henshaw's Night Lizard, after the discovery of X. h. gracilis. It was returned to full species status in 2001 when Lovich (2001 Herpetologica 57(4): 470-487) elevated X. gracilis to a full species. |
| Conservation Issues (Conservation Status) |
Although common throughout much of its range, this lizard is protected from collection. It needs exfoliated and fissured granite outcrops to survive. It takes thousands of years for this exfoliation and fissuring to occur, so this habitat will not be replaced for many centuries. When flakes and slabs are torn off rock outcrops by someone searching for this lizard or other reptiles, the habitat is irreparably damaged. Such rock destruction is illegal in California: "It is unlawful to use any method or means of collecting that involves breaking apart of rocks, granite flakes, logs or other shelters in or under which reptiles may be found." (2007 regulations 5.60.4.)
Reptile hunters are usually blamed for rock habitat destruction, but I have also witnessed people tearing off huge slabs of granite with a crowbar then carrying the slabs back to their truck to haul them away. Obviously, there are more threats to the habitat than just reptile collectors, and this law needs to be enforced in ways other than just protecting this lizard from collection or there will be no more habitat and no more lizards. |
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Taxonomy |
| Family |
Xantusiidae |
Night Lizards |
| Genus |
Xantusia |
Night Lizards |
Species
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henshawi |
Granite Night Lizard |
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Original Description |
Xantusia henshawi - Stejneger, 1893 - Proc. U.S. Natl. Mus., Vol. 16, p. 467
from Original Description Citations for the Reptiles and Amphibians of North America © Ellin Beltz
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Meaning of the Scientific Name |
Xantusia - honors Xantus, John
henshawi - honors Henshaw, Henry W.
from Scientific and Common Names of the Reptiles and Amphibians of North America - Explained © Ellin Beltz
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Alternate Names |
Xantusia henshawi henshawi
Henshaw's Night Lizard
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Related or Similar California Lizards |
X. gracilis - Sandstone Night Lizard
X. vigilis - Yucca Night Lizard
X. sierrae - Sierra Night Lizard
X. r. reticulata - San Clemente Night Lizard
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More Information and References |
Natureserve Explorer
California Dept. of Fish and Game
Stebbins, Robert C. A Field Guide to Western Reptiles and Amphibians. 3rd Edition. Houghton Mifflin Company, 2003.
Behler, John L., & F. Wayne King. The Audubon Society Field Guide to North American Reptiles and Amphibians. Alfred A. Knopf, 1992.
Grismer, L. Lee. Amphibians and Reptiles of Baja California, Including Its Pacific Islands and the Islands in the Sea of Cortés. The University of California Press, 2002.
McPeak, Ron H. Amphibians and Reptiles of Baja California. Sea Challengers, 2000.
Lemm, Jeffrey. Field Guide to Amphibians and Reptiles of the San Diego Region (California Natural History Guides). University of California Press, 2006.
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The following status listings come from the Special Animals List which is published several times each year by the California Department of Fish and Game.
This animal is not included on the Special Animals List, which indicates that there are no significant conservation concerns for it in California.
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Organization
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Status Listing
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| U.S. Endangered Species Act (ESA) |
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| California Endangered Species Act (CESA) |
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| California Department of Fish and Game |
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| Bureau of Land Management |
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| USDA Forest Service |
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| Natureserve Global Conservation Status Ranks |
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World Conservation Union - IUCN Red List
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